Resistant starch, weight loss and gut bacteria
What it found
In 37 people with excess weight, taking 40 g of resistant starch daily for 8 weeks led to an average weight loss of 2.8 kg and improved insulin sensitivity.
The benefits were linked to changes in gut bacteria.
What they found
Studies in people
Weight loss
After 8 weeks on resistant starch, participants lost an average of 2.8 kg more than when on control starch. Their fat mass and waist circumference also dropped.
Insulin sensitivity
Resistant starch improved glucose tolerance and insulin sensitivity compared with control starch. The glucose infusion rate during a clamp test rose significantly.
Gut bacteria changes
Resistant starch increased the abundance of Bifidobacterium adolescentis and Ruminococcus bromii, and decreased several other species. These changes were linked to lower BMI and better insulin sensitivity.
Inflammation and lipid absorption
People on resistant starch had lower levels of pro-inflammatory cytokines TNFα and IL-1β, and more fat excreted in their faeces, suggesting less fat absorption.
Animal and lab studies
Mice transplanted with human gut bacteria
Mice that received gut bacteria from people after resistant starch had less body weight and fat than mice given bacteria from control periods. Their glucose tolerance also improved.
B. adolescentis in mice
Mice given live B. adolescentis in their drinking water gained less weight and had less body fat on a western diet. The bacteria increased a protein that reduces fat absorption.
What the authors conclude
“RS supplementation for 8 weeks can help to achieve weight loss (mean -2.8 kg) and improve insulin resistance in individuals with excess body weight.”
Also in their conclusions
- They conclude that resistant starch (40 g per day, type 2) as a dietary supplement for 8 weeks can help achieve weight loss in individuals with excess body weight.
- They state that gut microbiota change driven by resistant starch was essential for its effect.
- They suggest that manipulating gut microbial composition through diet may represent a strategy for modifying host energy balance to promote health.
How it was done
The authors wanted to test whether resistant starch, a fermentable fibre, could help with weight loss in people, since previous human trials had not shown clear effects on body weight. They also wanted to find out if gut bacteria play a role.
They ran a randomised, placebo-controlled, double-blinded crossover trial in 37 overweight or obese adults in Shanghai, China. Each person took either 40 g of resistant starch or a control starch daily for 8 weeks, with a 4-week washout in between, while eating a balanced background diet. The study lasted 20 weeks per person.
What it can’t tell you
- The study was small (37 people) and had strict inclusion criteria, so the results may not apply to everyone.
- The long-term effects of resistant starch beyond 8 weeks are not known from this trial.
- The findings in mice may not directly translate to people.
Who paid
- Conflicts
- The authors declare no competing interests.
- Authors work at
- Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, China; The University of Hong Kong, China; Shanghai Jiao Tong University School of Medicine, China
The paper
- Title
- Resistant starch intake facilitates weight loss in humans by reshaping the gut microbiota
- Type
- Randomised controlled trial
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Cite
- Li H, Zhang L, Li J, et al (2024). Resistant starch intake facilitates weight loss in humans by reshaping the gut microbiota. Nature metabolism. doi:10.1038/s42255-024-00988-yFree full textPubMed 38409604DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error